The present invention relates to a karaoke network system constructed for serving a song data from a central station to a karaoke terminal through a communication line.
A conventional karaoke apparatus is constructed to sound an instrumental accompaniment of a requested song, which is mixed with a live vocal performance of a singer, while lyric characters of the requested song are displayed on a monitor. The conventional karaoke apparatus is classified into either of a stand-alone type and a terminal type. The stand-alone type of the karaoke apparatus is most widely spread out in the commercial market. The stand-alone type is equipped with a closed data source for storing a complete set of numerous song data required for karaoke performance in a self-support basis. However, the stand-alone type of the karaoke apparatus suffers from drawbacks such as the heavy cost of data storage and the difficulty of timely updating of song data.
On the other hand, the terminal type of the karaoke apparatus is connectable to a central station through a communication line to receive song data therefrom. This type can eliminate a closed data source which contribute to simplification of the karaoke apparatus.
A karaoke network system having the central station and the local karaoke terminals is classified into either a two-way communication type or a one-way broadcast type. In the communication type of the karaoke network system, the karaoke terminal transmits a request command to the central station through a telephone line, while the central station responds to the request command to thereby instantly transmit back requested song data to the requesting karaoke terminal. However, this communication type suffers from drawbacks such as heavy communication cost since a commercial telephone line must be called upon every request.
On the other hand, in the broadcast type of the karaoke network system, the central station successively broadcasts numerous pieces of song data in endless manner to all members of the karaoke terminals through a communication network composed of a cable line or a wireless line, while each karaoke terminal can pick up a desired one of the broadcasted song data pieces. Therefore, the karaoke terminal are free from a communication cost for two-way exchange of a request command and a corresponding song data. However, the broadcast type of the karaoke network system suffers in that the local karaoke terminal may occasionally wait for a long time until a desired song data piece is served. For example, the central station may successively broadcast a chain of 5000 song data pieces in an endless manner. In the worst case, the karaoke terminal must wait for an almost entire time length of the one complete chain if the karaoke terminal has just missed a desired song data piece in a preceding chain.